/* 
 * [New BSD License (BSD 3-Clause License)]
 * Copyright (c) 2012, Max Bechtold
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * 
 *     - Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     - Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *     - Neither the name of the Rel2Xml Project nor the
 *       names of its contributors may be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package maxbe.rel2xml.generator.dml;

/**
 * Equivalent of an SQL delete statement
 * 
 * @author Max Bechtold
 * 
 */
public class Delete extends AbstractDmlInstance {

	/** Table of which tuples are to be deleted */
	private Entity target;

	public Delete(String rootNodePath) {
		this.rootNodePath = rootNodePath;
	}

	public Entity getTarget() {
		return target;
	}

	public void setTarget(Entity target) {
		this.target = target;
	}

	@Override
	public String toXQuery() {
		String delete = super.toXQuery();
		String extVars = declareExtVars();
		if (!extVars.isEmpty())
			delete += extVars + "\n";

		String where = null;
		if (predicate != null)
			where = predicate.toXQuery(true);

		delete += String.format("delete nodes %s%s", rootNodePath, target
				.getTable().getXPathSelector());
		return delete + (where != null ? '[' + where + "];" : ";");
	}

	@Override
	public String toSQL() {
		String where = null;
		if (predicate != null)
			where = predicate.toSql();

		return String.format("delete\nfrom %s", target.getTable().getName())
				+ (where != null ? "\nwhere " + where : "");
	}

	@Override
	public String toString() {
		return toSQL();
	}

}
